What is ecological succession? Distinguish primary succession from secondary succession.

Explanation

The ocurrence of relatively definite sequence of communities over a long period of time in the same area resulting in estanblishment of stable or climax community is known as ecological or biotic suceession.
Primary Succession:
* It is also referred as .perisere. and is a type of biotic succession that occurs on a substratum deviod of any pervious life, like bare rock , sand dunes , new islands exposed out of the sea etc. where there was previously no life.
* Primay succession take a very long time (more than thousands of years in case of climax forest on bare rock) Process of primary succession occurs through a number of sequential steps , which follow one another . They are nudation , invasion , migration. ecesis, aggregation, competition, reaction , and stabilization. Secondary successions:
* It is the biotic succession that occurs in an area , which had an existing biotic community and has become bare due to destruction by fire , landslide , earthquake etc.
* The sequence of successional stages is called .subsere.,and time required for the completion of sere is much shorter than for primary seccession.